.sub-nav {
  display: flex;
  flex-wrap: wrap;

  li {
    width: 20%;

    a {
      width: 100%;
      height: 50px;
      display: flex;
      flex-direction: column;
      align-items: center;
      color: #666;
      font-size: 12px;

      i {
        display: block;
        width: 24px;
        height: 24px;
        background: url("../images/subnav-bg.png") no-repeat;
        background-size: 24px auto;
      }
    }
  }

  li:nth-child(2) a i {
    background-position: 0 -24px;
  }
}
